Exploring patient experiences of participating in a real and sham dry cupping intervention for nonspecific low back pain: A qualitative study

Background The current quality of evidence supporting dry cupping for individuals with chronic low back pain (CLBP) is low and suggests that nonspecific factors impact experiences reported by patients. Therefore, this study assessed the impacts of social and professional support on the experience of individuals with CLBP treated with dry cupping or sham. Method This is an observational study with qualitative approach. Twenty-four individuals with CLBP who received dry cupping or sham in a previous clinical trial were invited. Data was collected using a semi-structured interview conducted by a trained researcher. Content analysis was used to analyze experiences, systematic procedures, and description of the content of messages. The dimensions of “pain”, “general perceptions”, and “perceived social and professional support” guided the analysis. Results Answers of both groups converged on similar perceptions, especially regarding pain. Physical condition was the most fragile aspect. We also observed an influence of perceived social and professional support on painful symptoms. Thus, the experience of individuals with CLBP treated with dry cupping or sham indicated that factors related to social and professional support impacted results. Conclusions We observed that individuals with CLBP reported similar perceptions of the effects of dry cupping or sham treatment, indicating that contextual factors may influence the perception of these individuals regarding the treatment received.


Introduction
Chronic low back pain (CLBP) is a public health problem in several countries associated with high levels of pain and disability [1][2][3]. This condition is highly prevalent in males and females and negatively impacts quality of life [4]. In this sense, a multi-professional approach (including physiotherapists) is recommended for individuals with this condition [5].
Among therapeutic possibilities, dry cupping has been used [6,7] to reduce pain [8,9], improve physical function [8,10], and promote better quality of life of individuals with CLBP [11,12].However, the current quality of evidence supporting the technique is low [10], and its effects may not be superior to sham [7,13]. Therefore, improvements observed in individuals with CLBP after dry cupping may be due to nonspecific factors, such as therapeutic alliance. This notion is defined as the positive connection between therapist and patient, generated by a collaborative relationship based on professional support, empathy, and mutual respect [14], which may improve therapeutic intervention results and influence psychological and general health status, physical function, and perception of patients to the treatment [15][16][17].
Although specific interventions may not fully explain therapeutic results [18], the influence of nonspecific factors (including therapeutic alliance) on therapeutic results of individuals with CLBP must be assessed [19]. In this sense, comprehending all components responsible for clinical outcome alterations may help understand therapeutic changes, improve professional practice, and develop more effective approaches [20].
Therefore, this study aims to analyze the perceived experience of individuals with CLBP submitted to real dry cupping treatment or sham and its association with the dimensions of pain, physical condition, and perceived social and professional support.

Design
This exploratory and descriptive study with a qualitative approach explored opinions and representations on the topic investigated. The content analysis proposed by Bardin [21] was used to analyze experiences, systematic procedures, and objectives for describing the content of messages. In this study, content analysis was structured in thematic categories, categorized, and grouped.
The Consolidated Criteria for Reporting Qualitative Research was used to ensure a complete and transparent reporting of this study [22]. All participants provided written informed consent, and the research ethics committee of the Federal University of Rio Grande do Norte, Faculty of Health Sciences of Trairi (FACISA/UFRN) approved the study (number: XXXXXXX).

Participants, recruitment, and sample size
Between February and July 2020, participants from an ongoing randomized controlled trial (RCT) study [23] (ClinicalTrials.gov-NTC03909672) who completed a 2-month intervention were consecutively invited to participate in this qualitative study. People were eligible for inclusion if presented low back pain for � 3 months, pain intensity between 3 and 8 on a numerical pain rating scale, age between 18 and 59 years, and body mass index of < 35 kg/m 2 . Exclusion criteria were: individuals who had ever been treated with dry cupping or were undergoing physiotherapy; presence of any contraindication for dry cupping therapy; presence of neurological, vestibular, visual, or auditory deficits that could interfere with assessments; signs of fractures, inflammatory diseases, infection, or tumors in the spine; radiating lumbar or sacroiliac pain; rheumatic diseases (e.g., fibromyalgia or ankylosing spondylitis); travel plans in the next two months; and those unable to properly complete the assessment for any reason.
Sample size was calculated based on saturation of responses obtained with participants since new interviews would add few elements to the discussion. Nevertheless, sample size could be defined according to the experience of researchers and theoretical understanding of what is proposed in the study [24]. From 90 participants (45 per group) enrolled in the RCT, a maximum of 33.3% (n = 30) was estimated to compose the sample. However, 24 patients agreed to participate in the study.

Data collection
A semi-structured interview was performed between February and July 2020 (six months after the and off the intervention) to collect data regarding the experiences of individuals with CLBP submitted to dry cupping or sham. Data obtained were evaluated according to Bardin [17] and Minayo [20].

Pre-interview interventions
The intervention protocol was published in detail elsewhere [25]. Initially, participants were informed about objectives and procedures of the study, followed by the intervention (dry cupping or sham). An experienced physiotherapist applied interventions individually in a quiet university outpatient clinic, with the participant positioned prone and relaxed [25]. Dry cupping therapy was applied using two acrylic size 1 cups (4.5 cm internal diameter) with a distance of 3 cm between each cup, bilaterally, and parallel to L1-L5 vertebrae. The real dry

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cupping group performed two suctions for 10 min, once per week, for eight weeks. Sham group received the same protocol; however, cups were prepared to release the negative pressure in a few seconds [25]. During the study, interactions between therapists and patients occurred only during application of the technique (Fig 1).

Post-intervention interview
Interviews were performed to obtain information regarding experiences and understand the perception of individuals regarding the technique (dry cupping or sham) six months after the protocol. All interviews were conducted by an experienced physiotherapist not involved with other study procedures. She was a graduate student and research volunteer at the time of the study.
Data were collected by telephone, and participants were also allowed to write impressions, photograph, and send to researchers using messaging applications. Technological resources captured responses in full and provided information to create a qualitative database. Pseudonyms were assigned to participants for confidential purposes, and all answers were stored in folders and individually analyzed. Participants were allowed to report perceptions, without time or character limitation, while responding to the following questions: 1) "Tell us a little about the experience with dry cupping treatment"; 2) "How do you perceive social and professional support during the treatment?". The way of directing questions encouraged participants to freely express perceptions regarding the treatment in the dimensions of pain, general perceptions, and perceived social and professional support. These dimensions were defined based on reports and complaints of participants during the intervention and reflections consulted previously [26][27][28].

Data analysis
Reports were transcribed and reviewed according to consistency of established questions. In the end, another researcher (KMSC) described and categorized opinions into the following dimensions of treatment effects: pain, general perceptions, and perceived social and professional support. Subsequently, we identified dimensions corresponding to perceptions, highlighted in the text, and grouped using an analytical framework. As suggested by Minayo [20], statements were carefully interpreted, and investigated contexts were considered to decompose data and identify relationships between perceived experience and dimensions.

Results
Twenty-four individuals (16 female and 8 male, mean age of 23 ± 6.3 years) were included; eleven individuals completed high school. As shown in Table 1, twelve individuals composed each group. Categorization, grouping, interpretation, and data presentation using a qualitative approach were valuable for this study since the perceived effects varied between participants. Thus, the design of treatment dimensions was related to descriptions during treatment (Box 1).
As shown in Boxes 2 and 3, results regarding treatment perception were analyzed following the order of data description, analysis, and interpretation. Participants from real dry cupping group were assigned with the acronym RG followed by a number, whereas perceptions of participants from sham group were identified using the acronym SG followed by a number.  Social support started from the moment the "service" was offered free of charge to the population, benefiting not only the community but also the professionals and students involved in the project, whose aim was to improve the already studied practices." SG2 "The professional support became the differential in the dry cupping treatment, helped in the physical aspect, enabled better performance of the process and ended up [. . .] assisting psychological issues since it was a moment of relaxation and distraction."

Pain and general perceptions
Perceptions of participants from both groups were similar, especially regarding pain since it is a notorious context easily perceived through positive or negative impacts. In this sense, expressions were intentionally directed to the dimension of pain, while the dimension of general perceptions was ignored or intrinsic to pain. It is worth noting that the real dry cupping group (RG) indicated pain relief during the procedure, and the return of symptoms was less intense. Complaints regarding unsuccessful results were also reported, but to a lesser extent, in the face of expectations for treatment. Although other participants received a sham approach, the reported experience and benefits in the dimension of pain were satisfactory and recommendable to other people. As expected, some participants did not report any symptom change. Therefore, general perceptions and perceived support indicated that physical condition was the weakest aspect in this study since dry cupping presented visible physical repercussions (i.e., purple marks) that could result in dissatisfaction. However, improvements inherent to general perceptions (i.e., flexibility, sleep quality, relaxation, and relief from daily exhaustion) also deserve attention.

Perceived support: Social and professional
Regarding the dimension of perceived social and professional support, the influence of support received by people involved in the personal or professional context on painful symptoms was substantial. The considerable involvement of participants of both groups with this dimension can also be highlighted, such as "family support as a determining factor for treatment continuation", "friends support", "social stratification regarding the technique used", "horizontal therapist-patient relationship", "reception, ethics, and clarifications", and "listening, dialogue, and encouragement". Participants considered these aspects as fundamental elements in the care process, with positive impacts on physical, well-being, and emotional and psychological condition.

Discussion
To our knowledge, this is the first qualitative study aiming to understand the influence of social and professional support on experiences of individuals with CLBP treated with dry cupping. All individuals reported positive and similar perceptions in all dimensions after treatment, regardless of the technique used (real or sham).
The perception of pain improvement reported by most individuals of both groups can be explained by the expectation created before treatment [29] and other nonspecific factors, such as therapist-patient relationship [30], regression to the mean [31], and placebo effect [32]. To date, only one quantitative study observed significant improvements in pain after dry cupping compared with sham [8]. However, the study presented several methodological limitations (e.g., flaws in the randomization process and small sample size) that led to a questionable conclusion. In this sense, we conducted a clinical trial with good methodological quality to reduce bias observed in previous studies [23], in which we observed that the application of real or sham dry cupping showed no difference in the clinical improvement of patients with CLBP.
A recent systematic review also suggested that dry cupping reduced pain in patients with CLBP [7]; however, only two studies with high heterogeneity and without a comparative sham group were included in the review. Conversely, a small number of individuals receiving dry cupping therapy reported negative experiences in our study, probably due to the expectation created before treatment. This negative interpretation may be present in patients with pain since it is an individual experience influenced by other external factors [27,33].
Regarding physical condition, many participants reported no positive effects, which led us to believe that dry cupping did not favor this outcome. Nevertheless, it is worth noting that this aspect is strongly influenced by psychological, social, and physical factors [34,35]. A quantitative study observed that physical condition improved significantly after dry cupping compared with sham; however, the study also presented methodological limitations, such as inadequate randomization and lack of sample size calculation, blinding, and intention to treat analysis [7]. These biases may overestimate effects and generate doubtful results.
Individuals with CLBP, regardless of the technique received, reported satisfactory experiences about the received social and professional support. This may explain the positive results observed in the dimensions of pain and general perceptions since individuals receiving social support may present better results [36,37]. Reports regarding the presence of bruise or lack of previous experience with the technique corroborate with the study of Rossetini et al. [38], who stated that "new" or "innovative" therapies administered on the skin and with high marketing characteristics presented a great placebo effect. Therefore, the positive experience reported by individuals with CLBP treated with dry cupping or sham led us to understand the mechanisms of the technique and how participants perceived this "new" treatment. We also identified that the association between dry cupping and social and professional supports are essential for therapeutic success; thus, encouraging treatment continuation and, consequently, symptom relief.
The therapist-patient alliance can also be emphasized in our study. Both groups positively reported the presence of the physiotherapist in the symptom improvement process. Literature shows how this alliance benefits patients with CLBP [14]. It is worth mentioning that the treatment was individualized and performed in a temperature-controlled and cozy room [25]. As a result, attention was entirely focused on the individual, a factor that may generate positive effects.
This study presents limitations. We did not develop a focus group to understand the perceptions of collective efficacy or accurately identify divergences and convergences between therapeutic processes and treatment effects on CLBP symptoms. Despite this, our results can assist clinicians with CLBP management by understanding factors unrelated to the technique that also impact treatment success. Last, the presence of memory bias cannot be ruled out since the study was conducted six months after the clinical trial. Nevertheless, participants felt free to report experiences.
Our findings demonstrated that individuals with chronic low back pain presented similar perceptions of the effects of dry cupping and sham treatment. Therefore, improvements reported indicate that contextual factors, such as social and professional supports, potentiate the experience of participants. Writing -review & editing: Yago Tavares Pinheiro.